This invention relates to a networks management system including a plurality of agents and, in particular, to a network management system for switching a manager for managing the agents from an active one to a backup one, when a fault occurs in the active manager.
A network management system comprises first through N-th agents each of which carries out a management operation on a management object, where N represents a predetermined natural number which is not less than two, an active manager for managing the first through the N-th agents, and a backup manager for managing the first through the N-th agents, when a fault occurs in the active manager.
In prior art, a change from the active manager to the backup manager is carried out by using a changing device. More specifically, the changing device physically changes the active manager into the backup manager so as to change the connection of signal lines of the first through the N-th agents from the active manager to the backup manager, when the fault occurs in the active manager. Therefore, such a conventional method of changing from the active manager to the backup manager is called a physical changing method. The physical changing method is expensive. In addition, the physical changing method is incapable of easily switching from the active manager to the backup manager.